The present invention relates to a system providing remote control to medical apparatus, such as a respiratory ventilator for a patient. The system also provides a tactile expression of a parameter relating to a patient or a medical apparatus to a user of the apparatus. For example, the system may provide a tactile indication of a breathing characteristic of a patient connected to a ventilator to a clinician using the system.
In one aspect of the system of the present invention, a manual member has a handle with a moveable, trigger-like member. The handle and trigger are gripped by the user. When the trigger is squeezed by the user, a signal generator is operated to provide a control signal, through a cable or other suitable means, to the ventilator for use in controlling the apparatus. For example, the control signal may be used to control the supply of breathing gases to a patient.
Medical equipment, such as a ventilator, includes sensors providing signals corresponding to various parameters relating to a patient or the apparatus. In another aspect of the invention, a signal corresponding to a parameter, for example patient airway pressure, may be returned, or fed back, from the apparatus to a manual member having a trigger. The feedback signal drives an actuator for the trigger to cause the trigger to exert a force on the fingers of the user that indicates to the user the breathing characteristic of the patient.
In a preferred embodiment of the system, a single manual member is used for both control and feedback purposes.
Respiratory ventilators provide breathing gases to a patient via a breathing circuit. The breathing circuit typically has an inspiratory limb and an expiratory limb. One end of each of the inspiratory and expiratory limbs are connected to the ventilator. The other ends are connected to a Y-connector and through a patient limb to the patient. Pneumatic elements in the ventilator periodically provide breathing gases to the patient through the inspiratory limb during inhalations. On expirations, the breathing gases are discharged from the lungs of the patient into the expiration limb. Controls in the ventilator establish parameters, such as breaths/minute, tidal volume, maximum pressures, etc. that characterize the ventilation provided to the patient by the ventilator.
A patient may also be manually ventilated by means of a flexible container or “bag” provided on the ventilator. The bag is filled with breathing gases and manually squeezed by a clinician to provide breathing gases to the patient. Use of the bag, or “bagging the patient,” is often required or preferred by clinicians as it enables the clinician to physically control the delivery of breathing gases to the patient. Equally important, the feel of the bag as it is manipulated by the clinician enables the clinician to sense conditions in the lungs and respiration of the patient. In the hands of a skilled clinician, subtle characteristics and/or changes in the lungs and respiration can be sensed. It is difficult or impossible to obtain this type of feedback information when mechanical ventilating apparatus provides the breathing gases.
For the foregoing reasons, patients are often bagged during surgical procedures when anesthesia is induced in the patient by entraining an anesthetic in the breathing gases. Another environment in which patients are often bagged is in an intensive care unit.
However, if bagging is carried out for a long time, it becomes fatiguing to the clinician lessening both the fineness of the control of breathing gas supply and the sensing of lung or other respiratory conditions affecting the subject.
Also, the bag is usually positioned at a fixed location on the ventilator. This restricts the degree to which the clinician, when bagging a patient, can move about the patient, for example, to observe a surgical patient positioned in a manner appropriate to the surgery to be performed. The same is true when the pneumatic elements of the ventilator, rather than the bag, are providing the breathing gases to the patient since the controls necessary to operate the pneumatic elements are placed at a fixed location on the ventilator.
It is further recognized that current medical practice often requires several years of hands-on experience with a particular medical apparatus for a caregiver to become educated as to how to appropriately operate the apparatus to treat a wide variety of patient ailments. For example, the manual ventilation procedures described above are useful to treat many different respiratory ailments. Current practice unfortunately requires the caregiver to acquire several years of experience manually ventilating patients having different respiratory ailments in order to develop a sufficient understanding as to how to operate the device. Additionally, unique lung diseases may call for unusual practice that is not easily simulated in the field or classroom.
As such, it is desirable to provide a system and method that decreases the time necessary to train clinicians to operate medical apparatus to treat a wide variety of medical ailments. It is desirable to provide a system and method that is easy to use in either a classroom or hospital setting, and that allows the experienced and inexperienced clinician to move about a patient and medical apparatus while operating the apparatus. It is further desirable to provide a system and method that is easily adjusted to provide tactile feedback representative of a wide variety of patient ailments and symptoms.